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1.
Methods Mol Biol ; 2755: 167-178, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38319577

RESUMEN

Hypoxia is a common condition in rapidly proliferating tumors and occurs when oxygen delivery to the tissue is scarce. It is a prevalent feature in ~90% of solid tumors. The family of HIF (hypoxia-inducible factor) proteins-HIF1α and HIF2α-are the main transcription factors that regulate the response to hypoxia. These transcription factors regulate numerous downstream gene targets that promote the aggressiveness of tumors and therefore have been linked to worse prognosis in patients. This makes them a potential biomarker to be tested in the clinical setting to predict patient outcomes. However, HIFs have been notoriously challenging to immunolabel, in part due to their fast turnover under normal oxygen conditions. In this work, we developed a multiplexed immunofluorescence (mIF) staining protocol for the simultaneous detection of HIF1α and HIF2α in the same formalin-fixed paraffin-embedded (FFPE) tissue section.


Asunto(s)
Factor 1 Inducible por Hipoxia , Neoplasias , Humanos , Adhesión en Parafina , Hipoxia , Oxígeno , Neoplasias/diagnóstico , Técnica del Anticuerpo Fluorescente , Formaldehído
2.
Methods Mol Biol ; 2755: 149-163, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38319576

RESUMEN

Hypoxia occurs due to inadequate levels of oxygen in tissue and has been implicated in numerous diseases such as cancer, diabetes, cardiovascular, and neurodegenerative diseases. Hypoxia activates hypoxia-inducible factors (HIF) which mediate the expression of several downstream genes. Within the context of cancer biology, these genes affect cellular processes including metabolism, proliferation, migration, invasion, and metastasis. Pimonidazole hydrochloride (HCl) is an exogenous marker that is reduced and binds to thiols under hypoxic conditions resulting in adducts that can be visualized using antibodies such as Hypoxyprobe™. This chapter describes a method for using Hypoxyprobe™ to detect hypoxic areas in frozen and FFPE mouse samples by immunofluorescence (IF) and immunohistochemistry (IHC) staining.


Asunto(s)
Hipoxia , Neoplasias , Animales , Ratones , Oxígeno , Coloración y Etiquetado , Anticuerpos
3.
Cancers (Basel) ; 15(4)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36831670

RESUMEN

Breast cancer is the most diagnosed cancer in women in the world. Mebendazole (MBZ) has been demonstrated to have preclinical efficacy across multiple cancers, including glioblastoma multiforme, medulloblastoma, colon, breast, pancreatic, and thyroid cancers. MBZ was also well tolerated in a recent phase I clinical trial of adults diagnosed with glioma. The mechanisms of action reported so far for MBZ include tubulin disruption, inhibiting angiogenesis, promoting apoptosis, and maintaining stemness. To elucidate additional mechanisms of action for mebendazole (MBZ), we performed RNA sequencing of three different breast cancer cell lines treated with either MBZ or vehicle control. We compared the top genes downregulated upon MBZ treatment with expression profiles of cells treated with over 15,000 perturbagens using the clue.io online analysis tool. In addition to tubulin inhibitors, the gene expression profile that correlated most with MBZ treatment matched the profile of cells treated with known hypoxia-inducible factor (HIF-1α and -2α) inhibitors. The HIF pathway is the main driver of the cellular response to hypoxia, which occurs in solid tumors. Preclinical data support using HIF inhibitors in combination with standard of care to treat solid tumors. Therefore, we tested the hypothesis that MBZ could inhibit the hypoxia response. Using RNA sequencing and HIF-reporter assays, we demonstrate that MBZ inhibits the transcriptional activity of HIFs in breast cancer cell lines and in mouse models of breast cancer by preventing the induction of HIF-1α, HIF-2α, and HIF-1ß protein under hypoxia. Taken together, our results suggest that MBZ treatment has additional therapeutic efficacy in the setting of hypoxia and warrants further consideration as a cancer therapy.

4.
Sci Rep ; 13(1): 521, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36627383

RESUMEN

Moisture recycling in precipitation is an important hydrological process, accounting for ~ 67% globally. North-east India, home to the world's wettest place, boasts vast wetlands and forest-cover. Despite its proximity to the coast, we find locally recycled moisture to be the primary annual source of rainfall (~ 45%). During the pre-monsoon season, the enriched δ18O (~ - 0.7 ‰) and high d-excess (~ 14 ‰) are ascribed to enhanced transpiration, owing to atmospheric instability which causes Nor'westers. During the Monsoon season, oceanic flux provides increased surficial moisture, enabling deep-localised convection via evaporation. Significant localised recycling, even during the Monsoon season is estimated (~ 38%), with predominantly high d-excess in precipitation during latter half of the monsoon with increased moisture contribution from floods in Brahmaputra (high d-excess). The increasing δ18O and d-excess during the post-monsoon season is associated with progressively lesser rainout history and increased localized recycling (~ 67%). In light of the dwindling wetlands and forest-cover, our study highlights their indispensable role in governing regional hydro-meteorology and water availability.


Asunto(s)
Lluvia , Humedales , Monitoreo del Ambiente , Bosques , Estaciones del Año
5.
Isotopes Environ Health Stud ; 59(1): 1-26, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36562740

RESUMEN

Stable water isotopes in ground-level vapour are key to estimating water exchange between geospheres. Their sampling, however, is limited to laser-absorption spectrometers and satellite observations, having inherent shortcomings. This study investigates diffusive kinetic fractionation during liquid condensation under supersaturated environment, providing a cost-effective, reliable way of sampling ground-level vapour isotopes (18O, 2H). Experiments were undertaken at three locations in India with 'liquid' samples collected from condensation of ambient air at 0°C. Simultaneously, pristine 'vapour' was sampled via cryogenic-trapping using liquid nitrogen-alcohol slush at -78°C. The 'liquid' condensed under supersaturation was progressively more depleted in 18O, and less enriched in 2H than expected under equilibrium fractionation, with an increasing degree of supersaturation expressed as saturation index (Si). This study revealed: (1) Si, molecular density, Rh, T together control the extent of isotopic kinetic fractionation. (2) The presence of diffusive concentration gradient inhibits the flow of heavier isotopes during liquid condensation. (3) The stochastic nature of the process cannot be explained using a physics-based model alone. The artificial neural network model is hence deployed to sample δ18O (δ 2H) within -0.24 ± 1.79‰ (0.53 ± 11.23 ‰) of true value. (4) The approach can be extended to ground-validate isotope-enabled general circulation models and satellite observations.


Asunto(s)
Gases , Vapor , Isótopos de Oxígeno/análisis , Nitrógeno , Fraccionamiento Químico
6.
Breast Cancer Res ; 24(1): 98, 2022 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-36578038

RESUMEN

Breast cancer is the most diagnosed cancer among women. Approximately 15-20% of all breast cancers are highly invasive triple-negative breast cancer (TNBC) and lack estrogen, progesterone, and ERBB2 receptors. TNBC is challenging to treat due to its aggressive nature with far fewer targeted therapies than other breast cancer subtypes. Current treatments for patients with TNBC consist of cytotoxic chemotherapies, surgery, radiation, and in some instances PARP inhibitors and immunotherapy. To advance current therapeutics, we repurposed mebendazole (MBZ), an orally available FDA-approved anthelmintic that has shown preclinical efficacy for cancers. MBZ has low toxicity in humans and efficacy in multiple cancer models including breast cancer, glioblastoma multiforme, medulloblastoma, colon cancer, pancreatic and thyroid cancer. MBZ was well-tolerated in a phase I clinical trial of adults recently diagnosed with glioma. We determined that the half-maximal inhibitory concentration (IC50) of MBZ in four breast cancer cell lines is well within the range reported for other types of cancer. MBZ reduced TNBC cell proliferation, induced apoptosis, and caused G2/M cell cycle arrest. MBZ reduced the size of primary tumors and prevented lung and liver metastases. In addition, we uncovered a novel mechanism of action for MBZ. We found that MBZ reduces integrin ß4 (ITGß4) expression and cancer stem cell properties. ITGß4 has previously been implicated in promoting "cancer stemness," which may contribute to the efficacy of MBZ. Collectively, our results contribute to a growing body of evidence suggesting that MBZ should be considered as a therapeutic to slow tumor progression and prevent metastasis.


Asunto(s)
Mebendazol , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Mebendazol/farmacología , Mebendazol/uso terapéutico , Integrina beta4 , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Línea Celular Tumoral
7.
J Neuromuscul Dis ; 9(4): 571-580, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35723113

RESUMEN

BACKGROUND: Hereditary muscle disorders are clinically and genetically heterogeneous. Limited information is available on their genetic makeup and their prevalence in India. OBJECTIVE: To study the genetic basis of prevalent hereditary myopathies. MATERIAL AND METHODS: This is a retrospective study conducted at a tertiary care center. The study was approved by the institutional ethics board. The point of the collection was the genetic database. The genetic data of myopathy patients for the period of two and half years (2019 to mid-2021) was evaluated. Those with genetic diagnoses of DMD, FSHD, myotonic dystrophies, mitochondriopathies, and acquired myopathies were excluded. The main outcome measures were diagnostic yield and the subtype prevalence with their gene variant spectrum. RESULTS: The definitive diagnostic yield of the study was 39% (cases with two pathogenic variants in the disease-causing gene). The major contributing genes were GNE (15%), DYSF (13%), and CAPN3 (7%). Founder genes were documented in Calpainopathy and GNE myopathy. The uncommon myopathies identified were Laminopathy (0.9%), desminopathy (0.9%), and GMPPB-related myopathy (1.9%). Interestingly, a small number of patients showed pathogenic variants in more than one myopathy gene, the multigenic myopathies. CONCLUSION: This cohort study gives hospital-based information on the prevalent genotypes of myopathies (GNE, Dysferlinopathy, and calpainopathy), founder mutations, and also newly documents the curious occurrence of multigenicity in a small number of myopathies.


Asunto(s)
Enfermedades Musculares , Estudios de Cohortes , Humanos , Enfermedades Musculares/diagnóstico , Enfermedades Musculares/epidemiología , Enfermedades Musculares/genética , Distrofia Muscular de Cinturas , Mutación , Estudios Retrospectivos
8.
Biochem J ; 478(22): 3977-3998, 2021 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-34813650

RESUMEN

Tunneling nanotubes (TNTs) are F-actin-based, membrane-enclosed tubular connections between animal cells that transport a variety of cellular cargo. Over the last 15 years since their discovery, TNTs have come to be recognized as key players in normal cell communication and organism development, and are also exploited for the spread of various microbial pathogens and major diseases like cancer and neurodegenerative disorders. TNTs have also been proposed as modalities for disseminating therapeutic drugs between cells. Despite the rapidly expanding and wide-ranging relevance of these structures in both health and disease, there is a glaring dearth of molecular mechanistic knowledge regarding the formation and function of these important but enigmatic structures. A series of fundamental steps are essential for the formation of functional nanotubes. The spatiotemporally controlled and directed modulation of cortical actin dynamics would be required to ensure outward F-actin polymerization. Local plasma membrane deformation to impart negative curvature and membrane addition at a rate commensurate with F-actin polymerization would enable outward TNT elongation. Extrinsic tactic cues, along with cognate intrinsic signaling, would be required to guide and stabilize the elongating TNT towards its intended target, followed by membrane fusion to create a functional TNT. Selected cargoes must be transported between connected cells through the action of molecular motors, before the TNT is retracted or destroyed. This review summarizes the current understanding of the molecular mechanisms regulating these steps, also highlighting areas that deserve future attention.


Asunto(s)
Comunicación Celular , Animales , Transporte Biológico , Línea Celular , Membrana Celular , Estructuras de la Membrana Celular/inmunología , Estructuras de la Membrana Celular/metabolismo , Estructuras de la Membrana Celular/ultraestructura , Humanos , Fusión de Membrana , Nanotubos/ultraestructura
9.
J Neurol Sci ; 428: 117583, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34375915

RESUMEN

BACKGROUND: As the health systems around the world struggled to meet the challenges of COVID-19 pandemic, care of many non-COVID emergencies was affected. AIMS: The present study examined differences in the diagnosis, evaluation and management of stroke patients during a defined period in the ongoing pandemic in 2020 when compared to a similar epoch in year 2019. METHODS: The COVID stroke study group (CSSG) India, included 18 stroke centres spread across the country. Data was collected prospectively between February and July 2020 and retrospectively for the same period in 2019. Details of demographics, stroke evaluation, treatment, in-hospital and three months outcomes were collected and compared between these two time points. RESULTS: A total of 2549 patients were seen in both study periods; 1237 patients (48.53%) in 2019 and 1312 (51.47%) in 2020. Although the overall number of stroke patients and rates of thrombolysis were comparable, a significant decline was observed in the month of April 2020, during the initial period of the pandemic and lockdown. Endovascular treatment reduced significantly and longer door to needle and CT to needle times were observed in 2020. Although mortality was higher in 2020, proportion of patients with good outcome were similar in both the study periods. CONCLUSIONS: Although stroke admissions and rates of thrombolysis were comparable, some work flow metrics were delayed, endovascular stroke treatment rates declined and mortality was higher during the pandemic study period. Reorganization of stroke treatment pathways during the pandemic has likely improved the stroke care delivery across the globe.


Asunto(s)
COVID-19 , Accidente Cerebrovascular , Control de Enfermedades Transmisibles , Humanos , India/epidemiología , Pandemias , Estudios Retrospectivos , SARS-CoV-2 , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/terapia , Tiempo de Tratamiento
10.
Ann Indian Acad Neurol ; 24(5): 668-685, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35002124

RESUMEN

BACKGROUND AND PURPOSE: Occurrence of stroke has been reported among patients with COVID-19. The present study compares clinical features and outcomes of stroke patients with and without COVID-19. METHODS: The COVID-19 Stroke Study Group (CSSG) is a multicentric study in 18 sites across India to observe and compare the clinical characteristics of patients with stroke admitted during the current pandemic period and a similar epoch in 2019. The present study reports patients of stroke with and without COVID-19 (CoVS and non-CoVS, respectively) seen between February 2020 and July 2020. Demographic, clinical, treatment, and outcome details of patients were collected. RESULTS: The mean age and gender were comparable between the two groups. CoVS patients had higher stroke severity and extent of cerebral involvement on imaging. In-hospital complications and death were higher among CoVS patients (53.06% vs. 17.51%; P < 0.001) and (42.31% vs. 7.6%; P < 0.001), respectively. At 3 months, higher mortality was observed among CoVS patients (67.65% vs. 13.43%; P < 0.001) and good outcome (modified Rankin score [mRS]: 0-2) was seen more often in non-CoVS patients (68.86% vs. 33.33%; P < 0.001). The presence of COVID-19 and baseline stroke severity were independent predictors of mortality. CONCLUSIONS: CoVS is associated with higher severity, poor outcome, and increased mortality. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and baseline stroke severity are independent predictors of mortality.

11.
Ind Psychiatry J ; 28(2): 306-311, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-33223727

RESUMEN

PURPOSE: The purpose is to find out the rate of nocturnal enuresis in school going children (5-12 years) and the risk factors associated with it. MATERIALS AND METHODS: The parents of children aged between 5 and 12 years studying in two primary schools in Ahmedabad completed a self-administered semi-structured questionnaire comprising of enuresis, sociodemographic profiles, and risk factors. Children with enuresis and those without were compared on demographic characteristics and risk factors using Chi-square and t-test for categorical and quantitative data respectively. The data were analyzed using SPSS version 17. RESULTS: The response rate was 86.54% as 1904 responses were collected out of 2200. The overall rate of nocturnal enuresis was 6.7% (according to Diagnostic and Statistical Manual of Mental Disorders, 5th Edition definition of nocturnal enuresis). As the age increased, the rate of nocturnal enuresis declined. A positive family history was seen in 36.6% of children with enuresis. Enuresis was found to be more frequently in lower socioeconomic class. It was a neglected problem, only 20.6% of children received some kind of treatment. CONCLUSION: The rate of nocturnal enuresis was 6.7% in school going children. Strong correlation was found with family history. Although the rate was high, most of the children with enuresis were not treated.

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